src/components/tabs/README.md
Create a widget of tabbable panes of local content. The tabs component is built upon navs and cards internally, and provides full keyboard navigation control of the tabs.
For navigation based tabs (i.e. tabs that would change the URL), use the
<b-nav> component instead.
<div>
<b-tabs content-class="mt-3">
<b-tab title="First" active><p>I'm the first tab</p></b-tab>
<b-tab title="Second"><p>I'm the second tab</p></b-tab>
<b-tab title="Disabled" disabled><p>I'm a disabled tab!</p></b-tab>
</b-tabs>
</div>
<!-- b-tabs.vue -->
Tip: You should supply each child <b-tab> component a unique key value if dynamically adding
or removing <b-tab> components (i.e. v-if or for loops). The key attribute is a special Vue
attribute, see https://vuejs.org/v2/api/#key.
Tabs support integrating with Bootstrap cards. Just add the card property to <b-tabs> and place
it inside a <b-card> component. Note that you should add theno-body prop on the <b-card>
component in order to properly decorate the card header and remove the extra padding introduced by
card-body.
<div>
<b-card no-body>
<b-tabs card>
<b-tab title="Tab 1" active>
<b-card-text>Tab contents 1</b-card-text>
</b-tab>
<b-tab title="Tab 2">
<b-card-text>Tab contents 2</b-card-text>
</b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-card.vue -->
When <b-tabs> is in card mode, each <b-tab> sub-component will automatically have the
card-body class applied (this class provides the padding around the tab content). To disable the
card-body class, set the no-body prop on the <b-tab> sub component.
<div>
<b-card no-body>
<b-tabs card>
<b-tab no-body title="Picture 1">
<b-card-img bottom src="https://picsum.photos/600/200/?image=21" alt="Image 21"></b-card-img>
<b-card-footer>Picture 1 footer</b-card-footer>
</b-tab>
<b-tab no-body title="Picture 2">
<b-card-img bottom src="https://picsum.photos/600/200/?image=25" alt="Image 25"></b-card-img>
<b-card-footer>Picture 2 footer</b-card-footer>
</b-tab>
<b-tab no-body title="Picture 3">
<b-card-img bottom src="https://picsum.photos/600/200/?image=26" alt="Image 26"></b-card-img>
<b-card-footer>Picture 3 footer</b-card-footer>
</b-tab>
<b-tab title="Text">
<b-card-title>This tab does not have the <code>no-body</code> prop set</b-card-title>
<b-card-text>
Quis magna Lorem anim amet ipsum do mollit sit cillum voluptate ex nulla tempor. Laborum
consequat non elit enim exercitation cillum aliqua consequat id aliqua. Esse ex
consectetur mollit voluptate est in duis laboris ad sit ipsum anim Lorem. Incididunt
veniam velit elit elit veniam Lorem aliqua quis ullamco deserunt sit enim elit aliqua
esse irure.
</b-card-text>
</b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-card-no-body.vue -->
Note: Setting the no-body prop on <b-tab> will have no affect when <b-tabs> is not in
card mode (as the card-body class is only set when in card mode).
Refer to the Cards documentation for more details on card components.
Tabs use the tabs styling by default. Just add pills property to <b-tabs> for the pill style
variant.
<div>
<b-card no-body>
<b-tabs pills card>
<b-tab title="Tab 1" active><b-card-text>Tab contents 1</b-card-text></b-tab>
<b-tab title="Tab 2"><b-card-text>Tab contents 2</b-card-text></b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-pills.vue -->
Force your <b-tabs> controls to extend the full available width.
To proportionately fill all available space with your tab controls, set the fill prop. Notice that
all horizontal space is occupied, but not every control has the same width.
<div>
<b-tabs content-class="mt-3" fill>
<b-tab title="First" active><p>I'm the first tab</p></b-tab>
<b-tab title="Second"><p>I'm the second tab</p></b-tab>
<b-tab title="Very, very long title"><p>I'm the tab with the very, very long title</p></b-tab>
<b-tab title="Disabled" disabled><p>I'm a disabled tab!</p></b-tab>
</b-tabs>
</div>
<!-- b-tabs-fill.vue -->
For equal-width controls, use the justified prop instead. All horizontal space will be occupied by
the controls, but unlike using fill above, every control will be the same width.
<div>
<b-tabs content-class="mt-3" justified>
<b-tab title="First" active><p>I'm the first tab</p></b-tab>
<b-tab title="Second"><p>I'm the second tab</p></b-tab>
<b-tab title="Very, very long title"><p>I'm the tab with the very, very long title</p></b-tab>
<b-tab title="Disabled" disabled><p>I'm a disabled tab!</p></b-tab>
</b-tabs>
</div>
<!-- b-tabs-justified.vue -->
To align your tab controls, use the align prop. Available values are left, center and right.
<div>
<b-tabs content-class="mt-3" align="center">
<b-tab title="First" active><p>I'm the first tab</p></b-tab>
<b-tab title="Second"><p>I'm the second tab</p></b-tab>
<b-tab title="Disabled" disabled><p>I'm a disabled tab!</p></b-tab>
</b-tabs>
</div>
<!-- b-tabs-alignment.vue -->
Visually move the tab controls to the bottom by setting the prop end.
<div>
<b-card no-body>
<b-tabs pills card end>
<b-tab title="Tab 1" active><b-card-text>Tab contents 1</b-card-text></b-tab>
<b-tab title="Tab 2"><b-card-text>Tab contents 2</b-card-text></b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-bottom.vue -->
Caveats:
pills variant. When using the default tabs
variant, you may want to provided your own custom styling classes, as Bootstrap v4 CSS assumes the
tabs will always be placed on the top of the tabs content.Have the tab controls placed on the lefthand side by setting the vertical prop to true. Vertical
tabs work with or without card mode enabled.
<div>
<b-card no-body>
<b-tabs pills card vertical>
<b-tab title="Tab 1" active><b-card-text>Tab contents 1</b-card-text></b-tab>
<b-tab title="Tab 2"><b-card-text>Tab contents 2</b-card-text></b-tab>
<b-tab title="Tab 3"><b-card-text>Tab contents 3</b-card-text></b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-vertical.vue -->
Visually move the tab controls to the right hand side by setting the end prop:
<div>
<b-card no-body>
<b-tabs pills card vertical end>
<b-tab title="Tab 1" active><b-card-text>Tab contents 1</b-card-text></b-tab>
<b-tab title="Tab 2"><b-card-text>Tab contents 2</b-card-text></b-tab>
<b-tab title="Tab 3"><b-card-text>Tab contents 3</b-card-text></b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-vertical-end.vue -->
The width of the vertical tab controls will expand to fit the width of the tab title. To control the
width, set a width utility class via the prop
nav-wrapper-class. You can use values such as w-25 (25% width), w-50 (50% width), etc., or
column classes such as col-2, col-3, etc.
<div>
<b-card no-body>
<b-tabs pills card vertical nav-wrapper-class="w-50">
<b-tab title="Tab 1" active><b-card-text>Tab contents 1</b-card-text></b-tab>
<b-tab title="Tab 2"><b-card-text>Tab contents 2</b-card-text></b-tab>
<b-tab title="Tab 3"><b-card-text>Tab contents 3</b-card-text></b-tab>
</b-tabs>
</b-card>
</div>
<!-- b-tabs-vertical-width.vue -->
Vertical placement visually works best with the pills variant. When using the default tabs
variant, you may want to provided your own custom styling classes, as Bootstrap v4 CSS assumes the
tab controls will always be placed on the top of the tabs content.
Note: overflowing text may occur if your width is narrower than the tab title. You may need additional custom styling.
To apply classes to the currently active control or tab use the active-nav-item-class and
active-tab-class props.
<div>
<b-tabs
active-nav-item-class="font-weight-bold text-uppercase text-danger"
active-tab-class="font-weight-bold text-success"
content-class="mt-3"
>
<b-tab title="First" active><p>I'm the first tab</p></b-tab>
<b-tab title="Second"><p>I'm the second tab</p></b-tab>
<b-tab title="Disabled" disabled><p>I'm a disabled tab!</p></b-tab>
</b-tabs>
</div>
<!-- b-tabs-classes.vue -->
Fade is enabled by default when changing tabs. It can disabled with no-fade property.
If you want to add extra tabs that do not have any content, you can put them in tabs-start or
tabs-end slot(s):
<div>
<b-tabs>
<!-- Add your b-tab components here -->
<template #tabs-end>
<b-nav-item href="#" role="presentation" @click="() => {}">Another tab</b-nav-item>
<li role="presentation" class="nav-item align-self-center">Plain text</li>
</template>
</b-tabs>
</div>
<!-- b-tabs-item-slot.vue -->
Use the tabs-start slot to place extra tab buttons before the content tab buttons, and use the
tabs-end slot to place extra tab buttons after the content tab buttons.
Note: extra (contentless) tab buttons should be a <b-nav-item> or have a root element of
<li> and class nav-item for proper rendering and semantic markup.
If you want to add custom content to tab title, like HTML code, icons, or another non-interactive
Vue component, this possible by using title slot of <b-tab>.
<div>
<b-tabs>
<b-tab active>
<template #title>
<b-spinner type="grow" small></b-spinner> I'm <i>custom</i> <strong>title</strong>
</template>
<p class="p-3">Tab contents 1</p>
</b-tab>
<b-tab>
<template #title>
<b-spinner type="border" small></b-spinner> Tab 2
</template>
<p class="p-3">Tab contents 2</p>
</b-tab>
</b-tabs>
</div>
<!-- b-tabs-title-slot.vue -->
Do not place interactive elements/components inside the title slot. The tab button is a link which does not support child interactive elements per the HTML5 spec.
The tab selectors are based on Bootstrap v4's nav markup ( i.e.
ul.nav > li.nav-item > a.nav-link). In some situations, you may want to add classes to the <li>
(nav-item) and/or the <a> (nav-link) on a per tab basis. To do so, simply supply the classname to
the title-item-class prop (for the <li> element) or title-link-class prop (for the <a>
element). Value's can be passed as a string or array of strings.
Note: The active class is automatically applied to the active tabs <a> element. You may
need to accommodate your custom classes for this.
<template>
<div>
<b-card no-body>
<b-tabs v-model="tabIndex" card>
<b-tab title="Tab 1" :title-link-class="linkClass(0)">Tab contents 1</b-tab>
<b-tab title="Tab 2" :title-link-class="linkClass(1)">Tab contents 2</b-tab>
<b-tab title="Tab 3" :title-link-class="linkClass(2)">Tab contents 3</b-tab>
</b-tabs>
</b-card>
</div>
</template>
<script>
export default {
data() {
return {
tabIndex: 0
}
},
methods: {
linkClass(idx) {
if (this.tabIndex === idx) {
return ['bg-primary', 'text-light']
} else {
return ['bg-light', 'text-info']
}
}
}
}
</script>
<!-- b-tabs-with-classes.vue -->
Sometimes it's preferred to load components & data only when activating a tab, instead of loading
all tabs (and associated data) when rendering the <b-tabs> set.
Individual <b-tab> components can be lazy loaded via the lazy prop, which when set doesn't mount
the content of the <b-tab> until it is activated (shown), and will be un-mounted when the tab is
deactivated (hidden):
<b-tabs content-class="mt-3">
<!-- This tabs content will always be mounted -->
<b-tab title="Regular tab"><b-alert show>I'm always mounted</b-alert></b-tab>
<!-- This tabs content will not be mounted until the tab is shown -->
<!-- and will be un-mounted when hidden -->
<b-tab title="Lazy tab" lazy><b-alert show>I'm lazy mounted!</b-alert></b-tab>
</b-tabs>
<!-- b-tabs-lazy-tab.vue -->
One can also make all tab's lazy by setting the lazy prop on the parent <b-tabs> component:
<b-tabs content-class="mt-3" lazy>
<b-tab title="Tab 1"><b-alert show>I'm lazy mounted!</b-alert></b-tab>
<b-tab title="Tab 2"><b-alert show>I'm lazy mounted too!</b-alert></b-tab>
</b-tabs>
<!-- b-tabs-lazy.vue -->
Keyboard navigation is enabled by default for ARIA compliance with tablists when a tab button has focus.
| Keypress | Action |
|---|---|
| <kbd>Left</kbd> or <kbd>Up</kbd> | Activate the previous non-disabled tab |
| <kbd>Right</kbd> or <kbd>Down</kbd> | Activate the next non-disabled tab |
| <kbd>Shift</kbd>+<kbd>Left</kbd> or <kbd>Shift</kbd>+<kbd>Up</kbd> | Activate the first non-disabled tab |
| <kbd>Home</kbd> | Activate the first non-disabled tab |
| <kbd>Shift</kbd>+<kbd>Right</kbd> or <kbd>Shift</kbd>+<kbd>Down</kbd> | Activate the last non-disabled tab |
| <kbd>End</kbd> | Activate the last non-disabled tab |
| <kbd>Tab</kbd> | Move focus to the active tab content |
| <kbd>Shift</kbd>+<kbd>Tab</kbd> | Move focus to the previous control on the page |
Disable keyboard navigation by setting the prop no-key-nav. Behavior will now default to regular
browser navigation with TAB key.
| Keypress | Action |
|---|---|
| <kbd>Tab</kbd> | Move to the next tab button or control on the page |
| <kbd>Shift</kbd>+<kbd>Tab</kbd> | Move to the previous tab button or control on the page |
| <kbd>Enter</kbd> or <kbd>Space</kbd> | Activate current focused button's tab |
Use the <b-tabs> v-model to control which tab is active by setting the v-model to the index
(zero-based) of the tab to be shown (see example below).
Alternatively, you can use the active prop on each <b-tab> with the .sync modifier to activate
the tab, or to detect if a particular tab is active.
Each <b-tab> instance also provides two public methods to activate or deactivate the tab. The
methods are .activate() and .deactivate(), respectively. If activation or deactivation fails
(i.e. a tab is disabled or no tab is available to move activation to), then the currently active tab
will remain active and the method will return false. You will need a reference to the <b-tab> in
order to use these methods.
<b-tab> from being activatedTo prevent a tab from activating, simply set the disabled prop on the <b-tab> component.
Alternatively, you can listen for the activate-tab event, which provides an option to prevent the
tab from activating. The activate-tab event is emitted with three arguments:
newTabIndex: The index of the tab that is going to be activatedprevTabIndex: The index of the currently active tabbvEvent: The BvEvent object. Call bvEvent.preventDefault() to prevent newTabIndex from
being activatedFor accessibility reasons, when using the activate-tab event to prevent a tab from activating, you
should provide some means of notification to the user as to why the tab is not able to be activated.
It is recommended to use the disabled attribute on the <b-tab> component instead of using the
activate-tab event (as disabled is more intuitive for screen reader users).
v-model<template>
<div>
<!-- Tabs with card integration -->
<b-card no-body>
<b-tabs v-model="tabIndex" small card>
<b-tab title="General">I'm the first fading tab</b-tab>
<b-tab title="Edit profile">
I'm the second tab
<b-card>I'm the card in tab</b-card>
</b-tab>
<b-tab title="Premium Plan" disabled>Sibzamini!</b-tab>
<b-tab title="Info">I'm the last tab</b-tab>
</b-tabs>
</b-card>
<!-- Control buttons-->
<div class="text-center">
<b-button-group class="mt-2">
<b-button @click="tabIndex--">Previous</b-button>
<b-button @click="tabIndex++">Next</b-button>
</b-button-group>
<div class="text-muted">Current Tab: {{ tabIndex }}</div>
</div>
</div>
</template>
<script>
export default {
data() {
return {
tabIndex: 1
}
}
}
</script>
<!-- b-tabs-controls.vue -->
<template>
<div>
<b-card no-body>
<b-tabs card>
<!-- Render Tabs, supply a unique `key` to each tab -->
<b-tab v-for="i in tabs" :key="'dyn-tab-' + i" :title="'Tab ' + i">
Tab contents {{ i }}
<b-button size="sm" variant="danger" class="float-right" @click="closeTab(i)">
Close tab
</b-button>
</b-tab>
<!-- New Tab Button (Using tabs-end slot) -->
<template #tabs-end>
<b-nav-item role="presentation" @click.prevent="newTab" href="#"><b>+</b></b-nav-item>
</template>
<!-- Render this if no tabs -->
<template #empty>
<div class="text-center text-muted">
There are no open tabs
Open a new tab using the <b>+</b> button above.
</div>
</template>
</b-tabs>
</b-card>
</div>
</template>
<script>
export default {
data() {
return {
tabs: [],
tabCounter: 0
}
},
methods: {
closeTab(x) {
for (let i = 0; i < this.tabs.length; i++) {
if (this.tabs[i] === x) {
this.tabs.splice(i, 1)
}
}
},
newTab() {
this.tabs.push(this.tabCounter++)
}
}
}
</script>
<!-- b-tabs-dynamic.vue -->